Open pore architecture of an ordered mesoporous IrO2 thin film for highly efficient electrocatalytic water oxidation.

We report the first accessible channel-like open pore architecture of ordered 2D hexagonal mesoporous IrO2 films and its utilization as an efficient anode for electrocatalytic water oxidation. A well-ordered mesostructure of circa 7 nm pores were obtained by a facile one-pot soft-templating strategy, employing a [Ir(OH)6](2-) precursor stabilized by a triblock copolymer "Pluronic F127" as a pore-directing template. A mesoporous IrO2 film calcined at 400 °C (∼70 nm thick) affords a high surface area of 512 m(2)  cm(-3) and 2 times higher O2 evolution during the electrocatalytic water oxidation relative to an untemplated IrO2 coating film.